The present invention relates generally to reuseable sealing systems for containers and more specifically to a controlled pressure relieving dual sealing arrangement employing spaced gaseous and nongaseous fluid sealing means for use in conjunction with a liquid dispensing container.
In designing refillable pressurized liquid dispensing containers, it is necessary to provide secure sealing means to maintain the fluid under pressure and which sealing means must be designed to allow repeated removal and reinstallation of the closure member without damage thereto. Further, it is also desirable to incorporate into the container means for relieving any residual internal pressure from the container under controlled conditions so as to enable the container to be refilled.
Various sealing arrangements have been designed for use in conjunction with such containers; however, none of these arrangements have proven totally satisfactory. In one such design, a single seal is disposed in the closure member at a location so as to engage the outer edge portion of the container defining the opening therein. While this arrangement provides an adequate seal between the closure member and container, it is difficult to achieve a gradual release of internal pressure as venting will occur around the entire periphery of the opening simultaneously. Also, if the seal is to be positioned in the sidewall of the closure member, relatively complicated collapsable molding cores must be employed or other machining operations must be performed in order to provide a suitable recess for retaining the seal in position. While the seal could be positioned on the sidewall of the container adjacent the threaded portion, it may be damaged by the threads of the closure member passing across it if located adjacent the outer end. Positioning the seal on the container adjacent the inner end of the threaded portion is preferable to prevent damage to the seal, however, this may allow a portion of the container contents to accumulate within the threads thereby hindering removal of the closure member for refilling.
The present invention, however, provides a sealing arrangement for a pressurizable refillable dispensing container which overcomes these disadvantages by employing first and second spaced sealing means which are operative to effectively maintain the container in a pressurized condition and also operate to prevent the nongaseous contents of the container from entering and becoming trapped in the area of threaded engagement between the closure member and container. This sealing arrangement thus prevents contamination of as well as build-up of deposits on the mutually engaging threaded surfaces of the container and closure member which may result in sticking thereof, excessive wear of the threads over a period of time, or result in premature leakage. Additionally, because the nongaseous contents cannot become trapped within the area of threaded engagement, the possibility of the nongaseous contents being blown out onto the user when the container is opened are substantially reduced thus eliminating messy cleanup. Further, the sealing arrangement is particularly well suited for economical fabrication from suitable polymeric materials such as by a suitable molding process.
Controlled pressure relief means are also incorporated into the cover member which operate to gradually relieve internal pressure under controlled conditions as the closure member is partially removed from the container.
Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.